1. Field of the Invention
The invention relates generally to multi-layer electronic device packages, and more particularly, to routing signal traces in a multi-layer package.
2. Description of Related Art
Multi-layer electronic device packages, such as multi-layer printed circuit boards (xe2x80x9cPCBsxe2x80x9d) and multi-chip modules (xe2x80x9cMCMsxe2x80x9d), are well known in the art. Multi-layer packages include a plurality of substrate layers, with at least one of the outer substrate layers of the multi-layer package typically adapted to have electronic components mounted thereon. One or more of the substrate layers has conductive traces incorporated therewith that act as wires to interconnect the components mounted on the package. Other layers may provide power and ground connections to the components.
Incorporating conductive traces in multiple substrate layers allows circuit designers to lay out complex circuit designs using numerous interconnections between components, while minimizing the required surface area of the package. Electrical connections between the various substrate layers of the package, and between layers of the package and components mounted on the package, is achieved using xe2x80x9cvias.xe2x80x9d Basically, a via is a hole extending through substrate layers that is filled with conductive material to form an electrical connection.
Multi-layer packages are used extensively in computer systems and other semiconductor applications. The conductive traces of the multi-layer package may be used to route signals between components coupled to the package. Routing a high number of signals in a small areaxe2x80x94especially high-speed signalsxe2x80x94creates problems with parasitic noise generated from the signals routed through adjacent traces. This is especially problematic when multiple signal layers are employed for routing signals. This parasitic noise, sometimes also called xe2x80x9ccross-talk,xe2x80x9d may result in spurious logic errors.
The present invention addresses some of the above mentioned and other problems of the prior art.
In one aspect of the invention, multi-layer electronic device package includes first and second outer layers and at least one signal layer disposed between the outer layers. The signal layer includes signal traces and ground traces interleaved with the signal traces.
In another aspect of the invention, a method of routing signal traces in an electronic device package includes the acts of disposing a plurality of signal traces in at least one substrate layer, and interleaving a plurality of ground traces with the signal traces.
In a further aspect of the invention, a semiconductor device includes a first semiconductor die, a second semiconductor die, and a multi-layer package, with the first die and the second die mounted on the multi-layer package. The multi-layer package defines at least one signal layer. Each signal layer includes signal traces and ground traces interleaved therewith, with the signal traces interconnecting the first die and the second die.